Police Comics #80 (1948)

In "Penetro, Master of Solids," the disgruntled Professor Growley transforms himself into the intangible thief Penetro, using a revolutionary equation to phase through walls and steal rare treasures. When Plastic Man, disguised as a woman, sets a trap to catch him, Penetro's powers are turned against him in a moment of unexpected vulnerability.

In the countryside north of Midtown, a mysterious plant known as the strangleweed has ruined farms and driven desperate farmers to the city, where Officer Dan Richards encounters an old man begging for arrest out of sheer despair. Taking a personal interest, Dan investigates the strange phenomenon with his dog Thor, uncovering a web of deceit when a botanist’s seemingly noble efforts to study the weed clash with a sinister land-grabbing scheme.